1. Field of the Invention
The present invention relates to a contactless power transmitting system having an overheat protection function, which protects a battery cell module from damage due to overheating while the battery cell module is being charged, and a method thereof.
2. Description of the Related Art
Generally, a portable terminal such as a cellular phone, a personal digital assistant (PDA), or the like, includes a battery pack. The battery pack may be charged with a power supplied from an external charging apparatus, and may supply the charged power to the portable terminal for operation according to a manipulation of a user.
The battery pack may include a battery cell module charged with the power, and a circuit for charging and discharging the power in the battery cell module, among other components.
One method of electrically connecting the battery pack and the charging apparatus to each other is a direct contact between a terminal of the charging apparatus and a terminal of the battery pack.
However, when the two terminals contact each other or are separated from each other, because the terminal of the battery pack and the terminal of the charging apparatus have different potential differences, an instantaneous discharge phenomenon can occur. This instantaneous discharge phenomenon causes abrasion of the terminals, and creates a risk of an accident such as a fire or the like if foreign materials have accumulated in either terminal.
In addition, the electrical energy charged in the battery pack naturally discharges into the environment through the terminal of the battery pack due to moisture or the like, such that a lifespan of the battery pack may decrease and performance thereof may deteriorate.
Recently, contactless power transmitting systems, using methods of transmitting a power without a direct contact between terminals, have been suggested in order to solve several problems of the terminal connection method as described above.
In these contactless power transmitting systems, efforts to improve transmission efficiency of the power, as well as to stably transmit and receive the power, have been made.